The joining of reinforced concrete elements such as columns, walls, floors and beams is a well known activity in the building industry. The problems associated with this construction process are manifold and commonly is dependent on the connection of opposed reinforcement bars or rods that may or may not be accurately aligned in order to transfer tensile, compression and other forces through the connection.
Prior art connection means are as varied as the applications themselves. A common prior art method of connecting reinforcement bars is by lapping one bar with another with a preferable overlap length normally forty times the bar diameter. While this method does not require the overlapping bars to be accurately aligned it does create congestion within the confines of the concrete element. This has resulted in the concrete element which is typically a column sometimes having to be larger simply to accommodate the additional bars. This results in a coincidental degree of waste associated with this prior art method. Other methods used to join reinforcement bars utilise mechanical connectors which are generally threaded or attached by an epoxy adhesive joining the projecting ends of the reinforcement bars. This method however requires the bars to be perfectly aligned. Furthermore this method is only satisfactory if there is a single bar to be aligned with an opposite bar. Prior art disclosures of such connection methods include those disclosed in Australian Patents 2003210074 (Barfix Bermuda Ltd) which discloses a method and device for connecting reinforcing steel bars involving a connecting element comprising a thread cutting portion which cuts a screw thread in one of the reinforcing bars. The thread cutting portion cuts a conical screw thread forming a conical screw end on the reinforcement bar.
AU2001051968 discloses a structural bracing system wherein there is disclosed a lockable nut system for the use of threaded steel bar which includes a locking member which is slightly engaged with the bar. The locking member may have a finger to engage the nut with the end of the finger being displaced as a result of the deformation of a finger actuating tab.
WO98/44215 (Bartix Bermuda Ltd) describes a method and apparatus for interconnecting reinforcement bars wherein the connector cuts the thread in an opposing reinforcing bar as it is tightened.
In all of the above-mentioned prior art documents, the method and apparatus for joining reinforcing bars relies on the accuracy of aligning reinforcement bars of opposed separate columns. In many situations however there are multiple bars such as a cluster of bars which require connection in a group. There are a few prior art mechanical connection systems available that provide for a tolerance in a slight misalignment between respective bars. In order to connect one cluster of bars to another cluster of bars, it can be very difficult and labour intensive to ensure that each individual bar in one cluster is accurately aligned with its respective and complementarily opposed individual bar in another cluster. Furthermore where the reinforcement bars in concrete or steel elements are not aligned and able to be mechanically connected, the elements themselves require props or other temporary means to align or support them before connecting their respective reinforcement bars which is both time and labour intensive. Prior art examples of mechanical bar or rod couples include U.S. Pat. No. 5,305,573 A (BAUMANN), WO2011/113418 A1 (BILFINGER BERGER AG), WO 1992/008019 A1 (ARTEON) and WO 2007/061240 A1 (KIM).
In all prior art examples, while the principal function is to couple reinforcing rods and bars, even if they may be slightly misaligned (eg. WO 1992/008019 A1 (ARTEON)) there is no alignment function of the concrete elements or steel components themselves in which the bars are embedded. There is therefore a need for an apparatus and a method for not only joining reinforcement bars of separate opposed columns, but that also aligns the columns with each other without the use of props of other temporary means and wherein the apparatus is also able to function when opposing reinforcement bars are misaligned.